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A Loro Parque zoo drill left an employee injured after a confused veterinarian mistook the man — who was wearing a gorilla suit for the drill's procedures — for an actual animal and shot him in the leg with a tranquilizer.

The practice drill was meant to simulate the escape of a gorilla so that employees could be trained to respond properly — and the vet believed the man in the gorilla suit was a real one. As the employee scampered around the park during the drill, the vet shot him in the leg with a tranquilizer dose meant for a 400-pound gorilla. “The vet, who was only hired at Loro Parque two months ago, was supposed to stop the escaped gorilla,” a translated press release states. “The accident occurred during a police simulation of what should happen if a monkey were to escape the park.”

The man in the monkey suit reportedly had an allergic reaction, after which he was rushed to the hospital, the Dodo reported. However, according to an e-mail from the zoo sent to the Daily Mail, the man has recovered and is doing well. This isn’t the first time this particular zoo has been associated with violence or safety violations. In 2009, a zoo trainer was killed by a 6,600-pound orca whale, and past reports have shown employee complaints of dangerous working conditions.

According to Loro Parque, escape drills are carried out in zoos all over the world in order to practice proper responses to emergency situations in which animals are let loose accidentally.

“As part of the procedure, which took place in the security zone of the area and was only attended by authorized personnel of the park, they set off the emergency alarm used in this type of situation,” the zoo said in the e-mail to the Daily Mail. “Once the various activities and communications were carried out according to protocol, a keeper from the wild mammals team was struck by a tranquilizer shot that the vets use in this kind of situation… As a matter of course, Loro Parque, like all zoos and animal parks, regularly carries out this kind of emergency drill.”